Locomotive valve gear



March 4, 1931 iF, Hf BENTO 1,749,408

LOVCOMOTIVE VALVE GEAR Filed Feb. l0, 1927 .ifnorngy Patented Mar. 4, 1930 PATENT OFFICE FRANK H. BENTON, F TOPEKA, KANSAS LOCOMOTIVE VALVE GEARy Application led. February 10, 1927. Serial No. 167,092.

My invention more specifically statedrelates to an improvement adapted to the Walschaert valve gear employed on'locomotives whereby the starting power of a locomotive will be increased.

My invention has for its object the provisicnof means which may be readily applied to the Walschaert type of'valve gear, where' bythe travel of the steam control valve can be increased to any desired amount without,

however, producing unsatisfactory and undesirable angles or cramped conditions in the valve gear parts.

vThe Walschaert valve gear asiat present constructed and employed is limited in the amount of valve travel produced thereby, without introducing undesirable and unsatisfactoryv angles in the working arts of such valve gear. Furthermore, it 1s very often 2o diiiicult to obtain equalleads with the present type of Walschaert valve gear vbecause of certain conditions encountered on the locomotive. v

On ythe other hand, long valve travelfis quite desirable because itvnot only increases the starting power of a locomotive, but also permits of ak reduction in steam consumption.

-With my invention, means are provided for correcting the leads so that perfectly i -so equal leads can bey obtained at all points of the cut-off. n

The above enumerated objects and advan# tages of my invention, as well as other advantagesinherent inthe construction, will v all be more readily comprehended from the detailed description of the accompanying drawing, wherein y Figure 1 is anelevation of a portion of a locomotive and Walschaert valve gear provided with my improved means.

Figure 2 is a cross-section taken substantially on the line 2-2 of Figure 1, looking in the direction of the arrows.

y Figure 8 is a detail view in perspective of my improved lever element. V v

` lFigure 4'is a detail view in perspective of my improved valve rod.

f Inthe particular exemplification, merely portions of a locomotive, steam chest, cylinder and the running gear are shown; one end of the steam chest being shown at 10, and one end of its valve at 11. The adjacent end of the cylinder is shown at 12, with the steam introducing port 13 leading from the steam chest; while the piston-rod is shown at 14. The piston-rod 14 connects with the crosshead 15, which carries the usual wrist-pin 16 to which one end of the connecting or main rod 17 is secured.

A portion of the usual reach-rod, which connects with the lever in the locomotive-cab, is shown at 18; with the usual link 19 and radius bar or rod 20, the lower end of the link 19 being provided with the usual eccentric rod 21.

As the various elements thus far referred to are features of the well known type of Walschaert valve gear, a more detailed description thereof need not be entered into.

The steam chest or valve chamber head 22 is shown provided with a rearwardly extending bracket 23 which is preferably formed integral therewith. Mounted on the'opposite or inner side of the head 22, but not shown in the drawing, is the usual valvesteam cross-head toA which the usual lap and lead or combination lever 24 is connected by a pin indicated in dotted lines at 25. The lower end of the combination lever 24 is pivotally connected at 26 to the usual lap and lead connector or union link 27.

y My invention involves the introduction of a suitable lever 28 which is shown in detail in Figure 3. This lever 28 consists of a suitable casting or member of comparative thickness, provided adjacent to the upper end with an opening or pin receiving hole 29; at an intermediate point with a pin-receiving hole 30 which isy preferably surrounded, on both sides of the lever, with bosses as at 31, 31. The lever is preferably shown, somewhat enlarged toward the lower end 'which terminates in the laterally disposed bosses or trunnions 82, 32; the lever and trunnions being apertured to provide a pin-receiving hole 83 for pin 34 whereby the lever 28 ispivotally connected to the bracket 23; the pin 34 constituting the fulcrum point of lever 28.

As shown, the centers of openings 29 and 33 are in alignment, while the center ofopensol ' 34 of lever 28 and the 4point of connection 405 ing 30 is slightly off-set from a vertical line through the centers of openings 29 and 33.

I show lever 28 at top preferably provided with a lubricant-holding pocket or socket 34 which has ports leading from the bottom for conveying lubricant to the pins which are located in holes 29 and 30; while the enlargedtionlever 24 byineans of the rodor.link 37 'n whiclnis showngin detail,Figure 4. The link 371is preferably shown provided with.j bifurf. cated :ends 38,':39 5. the V,bifurcations38 :being f intended to.straddlethe.upper end of lever28 and is pivotally secured thereto, byvpin VX40.

whichy passes through; hole` 29vinlever 28;

while; the bifurcations 39Tshown spacedf; slightly farther apartare intendedtostrads dlethe upper endof the combinationglever 24,

'being pivotally; secured :thereto f ,by-y pin;l 4l the bifurcations at bothfendsof the v,link137 being, provided l' with' ,aligned pin-receiving holes 42 Fas shown in Figure .4.;

It is apparent, however, that thelever 28."I

andv link 37fmay.be` of any suitable-.construction.. -Y e n f In' operation, it -will be .seen that 'reciprocatoryniovemerlt 0f radius rod.20 willfiinpart movement to lever 28 about its fulcrum point 34thereby movinglink37.,v The combination lever is ,act'uatedby the valve rod 37\-aiid'the4k union-klink 121 eonj ointly; and as the combinationv lever 24 Ais alsoconnected through; 'thev4 mediumlof lpin 251and `the usual cross-head. (not shown)` withvalve-stem43 of thesteamivalve 11, it is evident the valve 11 is therefore also moved accordingly.

As radius -rod 20: is connected .-to, levery 28 ata pointY intermediateof the `fulcrum point with-link '37,) it ris apparent vthat the point 41 ^isk :given-greater movement lthan `point' 36 andi-as aresultthetravel-of-the valve llin the;V lstearnches t uis .also increased.. through movement of link, 37, conlleted with the lcombinatiorrl lever 24-wherebythevalve l1 is controlled.

, With` my-(invention,v all inequality.V of thev leads can be easily corrected byrmodifying thel slope` of the link, member i 37, namelyby raising or lowering its points Lofpivotal con-- nection.; vsuch `modification being dependent upon the lengthoflever 28 andthe location of its fulcrum point 'relative to the-lowerendofy the lever. .p

InV applying. my inventinr toA theI ,well known types, of -lalschaert` valve gears, the

only modifications that.'v need be Ymade f in such4 gear ,mechanism to correspondingly shorten the length of the radius' rod 20 and likewise change the radius of the link element 19; that is to say, the radius of link element 19 should be reduced( an amount equal to the'reduction in length of the radius rod 20. n

As previously described and as` shown in the exempliiication, the hole ,30,for pin 36 is shown somewhat rearward, relatively to the steam-chest, of a vertical line between pins 34 andv40gfthi`s beingdone to obtain uniform motion of llever 28 for the valvel gear mechanism as rillu's'rtrated in the drawing. It will beunderstood,however, that in certain constructions of gear mechanisms, it would be practicable to placethe opening 30 forkpin 36in a A.directvertical line withthe openings-1 29 pand! 33an'd again inotherinstances to place thebpening- 30 somewhat forwardcoff ,y thefvertical line between openings 29 andY 33.?

From vtheforegoing descriptionfand the disclosure` made in thedrawing, it -isap,-, parent that lmy invention, somewhat specifie; cally stat.edconsists in introducing 'a' startingy z power. leverfniechanism with certainfpiny conf.y nections andproviding a Ysuitable 'fulcrum or ,stationary Apin-.receiving member shown,in

the nature of a bracket 23 secured on the steamv chest vheady22; and while theinvention has been shownapplied to alwell known typeof; Walschaert valve gear mechanism in present;

use andhasbeen described-in termsusedA merelyV asterms of description and notas E,

termsAV of. limitation, vmodificationsY may be made without, however, departing from the spirit of my invention. v Y

l. In combination with avalved chamber.

head, .a valve stem ycross-head, a'flocomotive valvefgear involvinga combination lever and a-radius rod, a :rearwardly disposed bracket secured tothe `valve chamber head, a verti `v` cally'disposed lever fulcruniedfatfitsulower end on; said` bracket, a horizontally disposed link pivotally connected :at one 'end .:to fthe;-

upper end of said lever while theeother end.:k Y.

of the link is pivotally connected tothe upper end of.. the. combination leven ofthe -valve gear; aboveits `connection to the valve stem f cross head, while the radiusrod ofthe valve; gearis pivotally connected to saidfirst leverv at a point below the pivotalconnection oflsaidfrstflever with said horizontally disposed inkiv y f. i `V 2. In combination witha valved chamber head,.a ,valve Vstem -crossfhead, a locomotive valvegear'involv-ing a radiusbar-and a com'f bination lever, arearwardly disposed bracket securedto ,the valve chamber head, avertically disposed lever .providedwith three pin receiving yopenings therethrough, one of ksaid the lower.end,.while the third Ais at an intermediate point vadJacent Vto .the .first vmentioned opening, said leverx .having oil, vchambers in\ kopenings being at the'upperv end, a secondat l its top and sides communicating with said pin-receiving openings, the lower end of said lever being fulorumed on said bracket, While the intermediate pin receiving opening provides pivotal connection with the radius bar of the valvev gear, and a horizontally disposed link having bifurcated ends With one end pivotally connected at the upper pin receiving opening of said levell While the other end l lo of said link is pivotally connected to the upperV end of the combination lever of the valve gear above the pivotal connection of saidcombination lever to the valve stem cross head of the locomotive.

l5 FRANK H. BENTON. 

